1. Field of the Invention
The present invention pertains to a runway or taxiway light fixture enclosure or transformer housing of the type which is embedded in the runway surface and a method of installing the light housing in accordance with various thicknesses of runway structure and clearance requirements for the light fixture itself.
2. Background
In the art of runway and taxiway aircraft guidance lights of the type which are typically mounted at ground level or substantially flush with the runway surface, it is often necessary to adjust the enclosure or housing for the light fixture in accordance with the overall thickness of the runway structure. In the case of directional type aircraft guidance lights it is also necessary to be able to adjust the position of the light support structure to provide for aiming the light beam along a specified azimuth.
U.S. Pat. No. 3,678,260 to E. W. Beal and assigned to the assignee of the present invention describes a typical aircraft guidance light of the type wherein the light assembly casing and cover are supported within an outer housing embedded in a concrete or asphalt runway. In the light assembly illustrated in the Beal patent the light fixture cover, which includes the mirror and lens, is arranged to transfer the weight of an aircraft running over the light cover to the concrete reinforcement or to the housing flange in an indeterminate manner. Moreover, in conventional housings heretofore used the flange is not of sufficient diametral extent as to be capable of transferring a substantial part of the weight of the aircraft to the concrete but instead transmits a substantial amount of the aircraft weight to the housing itself which can result in buckling of the housing. Prior art flanges are also of a design which is not particularly suited for preventing the transfer of rotational loads to the housing if an eccentric braking force is exerted by an aircraft tire on the light assembly cover during runover thereof.
Accordingly, there are several features in the provision of an aircraft guidance light housing and support flange arrangement which are desirable and which have not been provided by prior art housings or methods of installation associated therewith.